<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>手写签名</title>
</head>
<body style="margin: 0;">
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    <script>
        const cvs = document.getElementById('cvs')
        cvs.width = document.documentElement.clientWidth
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            ctx.moveTo(e.pageX, e.pageY)
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        cvs.addEventListener('mousemove', e => {
            if (isDrawing) {
                ctx.lineWidth = 10
                ctx.lineTo(e.pageX, e.pageY)
                ctx.stroke()
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        })
        cvs.addEventListener('mouseup', e => {
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    </script>
</body>
</html>